In lubricating systems it is typical to provide a cyclically operable lubricant pumping apparatus which is periodically activated to dispense a predetermined quantity of lubricant.
Since the metering of the flow of lubricant is adjusted to provide lubricating fluid sufficient for a substantial operating interval, the pump is typically operated to supply lubricant over a short span of time, usually of the order of 2-90 seconds, at intervals separated by substantially long periods which are usually of the order of hours.
The devices typically employed to provide such operation usually comprise a motor operated cam which rotates at a very slow rpm, typically obtained by the use of a reducing gear mechanism between the motor output and the cam. At brief time periods during each long time interval, the cam functions to activate a pump for dispensing a predetermined quantity of lubricant. Such mechanisms are both complicated and costly.